The present invention relates generally to stage separation ordnance systems used in multistage missile systems, and more specifically to a separable interstage ordnance bracket that permits the use of a field joint across an ordnance cable.
Multistage missile systems use stage separation charges to rapidly disengage adjacent missile stage structures during flight. A common configuration includes the use of a linear shaped charge which forms an annular stage separation percussion ring which circumscribes a flight separation joint between two adjacent missile stages. In operation this stage separation percussion ring detonates at the flight separation joint to separate the two missile stage structures, when the linear charge is ignited by a fast burning ordnance transfer fuse cable.
Multistage missile systems resemble the family automobile, in that they require routine maintenance and inspections to be performed periodically. For this reason, multistage missile systems have two types of joints that separate adjacent missile stages. The first is the flight separation joint, which separates during flight upon the detonation of the stage separation percussion ring. The second type of interstage joint is the field separation joint, which mechanically disengages while the missile is on the ground to provide access for field servicing.
The problem with field servicing and the use of the field separation joint is that the ordnance transfer cables (that cross between the two adjacent missile stages) also need to be separated when the joint is broken. Current practice uses two rigid halves bracketing a separation charge retainer, with a dowel pin serving as an alignment aid. This serves as a separable joint only at stage separation. Field servicing requires an extra service loop of ordnance line to permit detaching the line from the stepover bracket after separating the stages far enough to permit access to the bracket area.
The task of facilitating field stage separation when ordnance transfer cables traverse a field joint is alleviated, to some extent, by the systems disclosed in the following U.S. patents, the disclosures of which are incorporated herein by reference:
U.S. Pat. No. 2,770,283 issued to Baughman;
U.S. Pat. No. 2,959,129 issued to Warren;
U.S. Pat. No. 3,116,895 issued to Mitchum, Jr.;
U.S. Pat. No. 3,174,706 issued to Wagner;
U.S. Pat. No. 3,328,743 issued to Acord;
U.S. Pat. No. 3,374,457 issued to Herrick;
U.S. Pat. No. 4,264,115 issued to Chow; and
U.S. Pat. No. 4,711,177 issued to Foster et al.
The Baughman reference discloses a means to attach a booster rocket to an aerial missle. The attaching means is in the form of a mechanical connection with an automatic release. Release is attained by impinging high pressure gas on a pawl of the mechanical connection.
The Warren reference discloses an apparatus to connect stages of a missile and allow for quick release. The apparatus includes a flange on adjacent stages which are juxtaposed and held together by a band. The band, in turn, is held together by a quick release connector(s) operative upon release of pressure controlled by a timing device.
The Mitchum reference relates to apparatus to connect (or couple) a satellite to a rocket. Release of the structures follows an electrical pulse to actuate a motor that ultimately releases a spring in compression to exit a separating force. Wagner discloses a concept similar to Mitchum Jr. In this patent, separation of structure occurs upon activation of a plurality of cylinders which push a rod radially outward. Pressure to operate the cylinders is in the form of a fluid generated by a plurality of squibs. The squibs activate on a timed signal and the rods function to disengage individual clamp components to separate the satellite from the missile.
The Accord reference discloses a quick connect/disconnect electrical connector in the environment of a missile and an airplane. An electrical flow path through the connector provides for separation and disconnection of the same upon application of a force. Herrick discloses disconnect couplings for separably coupling adjacent stages of a multistage rocket or other type of space vehicle. Disconnection is attained without detrimental thrust or drag on the forward stage. The Foster patent discloses various ordnance detonation components in an auxiliary booster system.
Chow discloses a connector for connecting power and/or signal circuits between adjacent missile stages. The connector include individual housings mounted to respective missile stages at the line of flight separation between stages. A separation assembly is provided for disengaging the electrical contacts independently of the separation of the connector housings and the stages. The separation assembly includes a squib for generation of an expanding, pressurized gas.
While the above-cited references are instructive, the task remains to provide a connector which permits the components to be joined along a field separation joint, yet permit the components to separate and remain with the respective structures to which they are mounted when the stages separate along a different separation joint. The present invention is intended to satisfy that need.